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(No Model.) 2 Sheets-Sheet 1.

G. H. GOBLISS, Decd E. A. CORLISS,AdmiI1iStYatriX. MACHINE FOE BORING THE CYLINDERS 0F STEAM ENGINES.

No. 450,401. Patented Apr. 14,1891

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G. H. OORLISS, Deod.

j 2 Sheets- Sheet 2 (No Model.)

- v E. A. CORL1ss,Administrat1ix. MACHINE FOR BORING THE CYLINDERS 0F STEAM ENGINES No. 450,401. Patented Apr. 14, 1891.

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J/ dl/Mdna UNITED STATES PATENT FFICE.

EMILY A. CORLISS, OF PROVIDENCE, RHODE ISLAND, ADMINISTRATRIX OF GEORGE II. CORLISS, DECEASED.

' MACHINE FOR BORING THE CYLINDERS OF STEAM-ENGINES.

SPECIFICATION forming part of Letters Patent No. 450,401, dated April 14, 1891.

Application filed December 23, 1889. Renewed November 6, 1890. Serial l\To. 370,452. (No model.)

To aZZ whom it may concern:

Be it known that GEORGE 1-1. CORLISS, deceased, late a citizen of the United States, residentin the city and county of Providence,

5 in the State of Rhode Island, (represented by EMILYA. CORLISS, administratrix,) invented a new and useful Machine for Boring the Cylinders of Steam-Engines, of which the following is a specification.

It is essential that the piston-chamber of a steam-engine cylinder should be smoothly and evenly bored in true cylindrical form and in the proper relation to the other finished parts of the cylinder. The cylinder must be accurately centered and firmly held in the correct position, and means must be provided for removing the cutting-tools to repair or grind them and for their replacement in absolutely the same position on the boring-bar which they occupied before removal; and, further, since in order to insure a smooth finish it is necessary to bore the piston-chamber in two or more operations, the latter of which would be with a cutter- 2 5 head of greater diameter than the first, means must be provided for centering the larger cutter-head in the correct position relatively to the first.

Prior to this invention the piston-chamber 0 had been bored on the ordinary boring-mill, and the proper centering and adjustment of the cylinder upon the mill being dependent upon the care and skill of the workmen inaccuracies were found liable to occur, and imperfections of work often resulted from the necessary removal and replacement of the cutting-tools. These inaccuracies and imperfections necessarily required time and labor for their correction.

In thisinvention Mr. CORLISS has made provision for centering the cylinder with accuracy without dependence upon the carefulness or skill of the workmen, and for firmly holding it in the correct position for boring the piston-chamber to the proper smooth and true cylindrical form and in correct relation to the other finished parts of the cylinder, and other provision for accurately centering the cutting-tools and for insuring their accurate replacement after their removal for any cause, and also for bringing two or more cutter-heads of different diameters to'the same center on the boring-bar. In this machine the adjustment .of the cylinder or of the cutting-tools requires no verification or skilled labor. The adjustments are certain to be right, not only for the particular cylinder operated upon, but also for all cylinders of equal diameter. The same is true as to the adjustment of cutter-heads of equal or differing diameters.

In the accompanying drawings, Figure 1 is a plan view of the machine with a cylinder in place thereon. Fig. 2 is an elevation of the same. Figs 3 and 4 are respectively a front and side elevation of the cutter-head and tools. Fig. 5 is a longitudinal section on line X X of Fig. 3, showing the cutter-head and sleeve and the means for centering the head. Fig. 6 is a transverse section on line X X of Fig. 2. Fig. 7 is a central horizontal section through portionof the boring-bar and the adjacent parts. Fig. 8 is an end view of the same, with a portion of the cap broken away to show the inclosed gearing which communicates the feed motion. Figs. 9 and 10 are on a larger scale, showing the provision for holding and adjusting one of the cutters, Fig. 9 being a plan view, and Fig. 10 asection on the line on a: in Fig. 9. 50

Similar letters of reference indicate like parts where they occur in the drawings.

A represents the table or bed of the machine, which is a smooth plane surface, Mounted upon the table is a housing A, in which the boring-bar has its bearings. This boring-bar has no endwise movement, but is rotated by a worm w and a gear G, driven by power conveyed through bevel-gears in the well-known manner. A sleeve O is fitted upon the bar 13 and slides easily thereon, as actuated by a threaded shaft B, which engages a c0rrcspondingly-threaded nut 8, secured to said sleeve. The shaft B is loosely inclosed in a spline-groove in said boring-bar and revolves therewith. It also has a contemporaneous independent rotation within said bar to feed the cutter-head and tools longitudinally of said bar. It is driven and reversed by means of fast and loose pulleys 10o and connecting-gears operated in the ordinary way. Its rotation is controlled by means of gearing contained within a cap A bolted to the housing, said gearing being also connected with a bevel-gear and handle B F is a fast and F a loose pulley, on which a belt H is shifted at will from the pulley XV,

driven by any convenient means, (not shown,)

andfis a pii1ching-screw,wl1icl1 can at will hold the shaft fast when the belt is on the loose pulley. The gear-wheel F driven by the belt or held stationary by the pinching-screw f, conthe pinion b is held stationary, the revolutions of the boring-bar, carrying the wheel Z2 around the pinion b in the manner sometimes known as the sun-an d-planet motion, turns the feed-screw B and feeds the cutter-head D forward. The rate of such feed can be varied by changing the gears 19' and b \Vhen it is desired to reverse the feed, the screw f is relaxed and the belt H is shifted upon the fast pulley F, and thus the proper motion is communicated through the same gearing.

The sleeve C is provided with a flange C near its forward end and is tapered from said flange forward. It is also provided with a recess or annular groove 0, having tapering sides,and adapted to receive with a snug fit the double-tapered flange or ring (Z on the back of the annular cutter-head D. The cutter-head is constructed in two sections, which are-rigidly secured together in the form of a ring by bolts d. The central orifice in the cutter-head is turned to fit the taper on the end of the sleeve C. Bolts 22, inserted through the flange C and tapped into the head D, serve to draw the cutter-head into the proper position, while the ring (I engages the groove 6 and thereby accurately centers the head D. When a large cutter-head is substituted for a small one, the same means bring it to the correct position and center on the boring-bar. Cutting-tools c are removably fixed upon inclined seats in the periphery of the cutter-head, and

each tool is longitudinally adjustable on. its inclined seat. To effect the adjustment, the screw 6 Figs. 9 and 10, is slackened and the wedge e slightly lifted. This relaxes the hold on the cutter e, which is then moved forward or backward, as required, after which the wedge e is again forced home and the screw 6 again tightened.

Jigs a a, bolted to the bottoms of the exhaust-valve boxes previously prepared, and also to the table A by bolts inserted in previously-determined slots a a in said table and valve-box bottoms, serve to accurately center the cylinder on the machine and to hold &50,401

it firmly in the correct position. 'lhejigs are of a height suited to the cylinder ope *ated upon, being of sufficient height in every case to support the cylinder with its center line exactly coinciding with the axis of the boring-bar. Consequently a cylinder of large diameter would not require so high jigs as would a cylinder of small diameter.

When the cylinder is brought to this machine, the hole for the piston-rod packing-box has been bored in the closed end and the forward end of the boring-bar takes a bearing in bushing inserted in such hole. The bar is thus supported at each end and the cutterhead is operated on such bar between such supports.

The sectional construction of the cutterhead D allows its easy removal and replacem ent on the sleeve 0 Without removing the cylinder.

1 claim as the invention of said GEORGE II. OoRLIss and desire to secure by these Letters latent- 1. An annular cutter head D, composed of two sections removably secured together with their ends abutting, said head having a tapering central opening and a double-tapered flange d, concentrically surrounding the same, a sleeve C, tapered at one end and provided with a surrounding concentric flange C, and a double-tapered annular groove 0, combined with each other and with means, as the bolts n, for drawing the flange (Z of the head into the double-tapered groove 0 in the flange C of the sleeve, and adapted to serve as specilied.

2. The annular cutter-head D, constructed in sections removably secured together, in combination with a sleeve C, tapered and flanged as shown, and with bolts d for holding the sections together, and with bolts n for holding them to the sleeve, and with aseries of cutting-tools 6, carried in the cutter-head and adjustable in inclined seats in the outer face thereof, all substantially as herein specified.

3. A machine for boring the piston-chamber of steam-engine cylinders and for analogous purposes, composed of the following elements in combination: a plane table provided with slots or openings in predetermined positions, jigs similarly provided with predetermined holes, bolts for securing such jigs upon the table in the correct position, and other bolts for securing and centering the cylinder on such jigs to hold its center line in coincidence with the center line of the boring-bar, a housing mounted upon said plane table, and supporting means for operating a boring-bar, a boring bar carried on such housing, a threaded shaft contained withinsueh boringbar and also arranged for independent rotation within such bar while being revolved therewith, a sleeve arranged to slide upon said bar as actuated by said threaded shaft and provided with means, as a threaded nut,

my hand in presence of two subscribing wit- 1o nesses.

EMILY A. CORLISS,

Admtn'istmtrtx of the estate of George H. 001"- Z'iss, deceased.

Witnesses:

HENRY MARSH, Jr. MARIA L. CoRLIss. 

